Illuminated sign



May 12, 1936 H. M. JOHNSON ET AL n2,040,695

ILLUMINATED S IGN Filed Sept. 27, 1929 2 Sheets-Sheet- 1 May 12, 1936. H. M. JOHNSON T AL ILLUMINATED S IGN Filed sept. 27, '19.29

2 Sheets-Sheet 2 Patented May 12, 1936 PATENT OFFICE ILLUMINATED SIGN Harold M. Johnsonand Albert C. Perbal, St. Louis, Mo.; said Johnson assignor to said Perbal Application September 27, 1929, Serial No. 395,530

15 Claims.

This invention pertains to illuminated signs or signals and more particularly to that type of sign in which the lettering or other symbol is rendered visible by`being made luminous by means of incandescentl gas. Such signs are com-A monly known as neon signs although other gases than neon may be used in their construction.

In the operation of these incandescent tube signs it has been found that the quality of the illumination depends greatly upon the pressure or the degree of rarefaction of the gas which is rendered luminous by the passage of the electric current. It has also been .found that during the operation of such a sign a certain amount of the gas is lost by absorption or by being otherwise rendered unavailable for carrying the current by the continued operation of the tube.

This is an important matter Where the sign element consists of a short length of small tube since the volume of gas contained in such a small tube is small and a slight amount of absorption will make a considerable difference in the pressure or quality of the gas. On this account, trouble has been experienced `in the operation of such small tubes and it has been found tha their life is comparatively short.

One of the objects of this invention, therefore, is to provide a construction for such luminous signs or signal elements which will obviate the trouble due to deterioration of the gas by absorption, or otherwise.

Another object of this invention is to provide a construction in which a small sign or signal element may be used containing a small quantity of gas together with a reservoir for surplus gas which will provide an ample supply of gas to compensate for such deterioration.

Another object is to provide a sign or signal element which will be small in size and yet have a suicientA gas capacity to compensate for deterioration.

Another object is to provide a method and means for constructing sign or signal elements in such a way that small lettering may be used and still have sufficient gas vcapacity for a long life.

Another object is to provide simple and economical methods of construction for sign or signal elements of this type.

Further objects Will appear from the following description taken in connection with the accompanying drawings; in which:

Figure 1 is a side view of a sign element embodying this invention;

Figure 2 is a section on line 2-2, Figure 1;

Figure 3 is a sectional View similar to Figure 1 showing a special type of symbol or signal element.

Figure 4 is a section on line 4-4, Figure 3.

Figure 5 is a front View of a sign element illus- 5 trating a novel method of constructing such an element in accordance with this invention;

Figure 6 is a section on line 6 6 of Figure 5.

Figure 7 is a sectional view illustrating another embodiment of this invention; I

Figure 8 is a section on line 8 8, Figure '7.

Figure 9 is a similar view illustrating still an. other embodiment of this invention.

Figure l is a section on line l-ID of Figure 9.

Figure 11 is a sectional viewl illustrating the 15 construction of a tube sign in accordance with this invention.

Figure 12 is a section on line |2-I2 of Figure 1l. f

Figure 13 is a'sectional view similar to Figure 20 illustrating a system for constructing a sign by means of a series of letter units which may be assembled in any desired sequence.

Figure 14 is a section on line Il-Il of Figure 13.

Figure 15 is a face View of a section of a sign element illustrating a way of handling certain types of letters or symbols.

Figure 16 is a section on line iS-IG of Figure Figure 17 is a cross section of a sign or signal element illustrating a modiiied construction for such an element; and

Figure 18 is a similar section illustrating still another plan of construction.

In accordance with this invention a restricted path for an electric current is provided by suitable construction in such a. manner that said path can be lled with a suitable gas such as neon or the like in a proper state o f rarefaction, and a reservoir or container of comparatively large capacity as compared with that of the restricted current path which forms the sign element, is provided. The restricted path may be formed between transparent Walls such as the Walls of a. glass tube or plate which are transparent so that the gas rendered luminous by the passage of the current may be visible. The restricted path may thus be formed of a glass tube bent to the proper shape as in ordinary neon signs or it may be formed by a groove in a plate of glassv or other material covered by another plate so. as to close the groove in order to re- Vstrict the passage of the current'to the groove. 55

' terior of the tube I.

' face of the inner tube 3.

By this arrangement a circulation of gas maytake place so as to replenish the gas in the current path and thereby maintain the same in proper condition for a long time.

Referring now to the drawings, I designates a tube or container. In the embodiment illustrated in Figure 1 this container may consist of a glass tube having terminals or electrodes 2 sealed therein in any suitable manner. Mounted within the tube I is a second tubel 3 one of whose ends 4 is closed, while the other is open. The outside surface of the tube 3 has formed therein by pressing, molding, etching or otherwise, a groove 5. The groove 5 may be formed to the shape of any appropriate symbol such as the letters A, B, C, D shown in the drawings. The groove in this case is formed on the outside sur- The groove begins at 6 at one end of the tube 3 and follows continuously through all the letters, terminating at 'I at theother end of the tube 3. The groove is in cornmunication at the ends 6 and 1 and with the in- The tube I contains a suitable gas at a suitable pressure so as to become luminous when a current passes along the groove 5. The entire tube being filled with gas provides a reservoir of gas of much greater capacity than the groove 5. Accordingly, any absorption or deterioration lof gas in the groove 5 will have little or no effect upon the density of the whole body of gas. Since the gas can circulate freely through the groove 5, the supply thereof will always be maintained in said groove in good condition for transmitting current.

The fact that the end 4 of the tube 3 is closed makes it impossible for theelectric current to pass between the electrodes 2 thru the central portion of the tube. The end 4 thus forms a partition dividing the tube I into two compartments into each of which one of the ends 6 or 'I of the groove 5 opens.

When the current is supplied to the electrodes 2 it tends to. pass from one to the other of said electrodes through the intervening gas. `Since the tube 3 may be made a close fit in the tube I, little or no current will be able to pass between the peripheral portions of said tubes. Accordingly, the current is constrained to pass along the groove 5 which in fact forms a tube similar to the tubes of the ordinary neon sign. 'Ihe current is passed through this groove in suiiicient density. to cause the gas therein to become luminous.

This causes the letters formed by the groove to.

become luminous so that they may be read. No other part of the tube carries current in sufficient density to become luminous. Accordingly, only the lettering will be visible to an observer. 'I'hose parts of the lettering shown in dotted lines in Figure 1 are ordinarily concealed or otherwise rendered invisible, as for instance, by painting the outside of the tube I with an opaque paint in such portions thereof as to hide that part of the groove 5 whichis to be concealed. Another'way of accomplishing this purpose is to place in those parts of the groove 5 which are to be rendered invisible, strips 30 of conducting maa signal element of special form. This signal is intended to display a luminous path of helical or other vform passing around or along the tube. This element may be so used for sign borders and the like. It may be applied, however, to any other typeof sign or signal. In this case the groove 5 is formed upon the outer surface of two or more inner tubes 8. These tubes are similar in construction to the tube 3 except that their ends are formed toa special shape so as to match each other as indicated at 9 when the tubes are placed within the tube I with their matching ends together. The groove 5 may be formed so as to cross the junction 9 in the manner indicated in Figure 3. When so constructed the two tubes 8 are identical in form so as to be interchangeable. In this embodiment, the closed ends of the tubes at the junction 9 form a partition. which forces the current t'o pass along the groove.

Figures 5 and 6 illustrate an embodiment of this invention adapted for forming a sign element having script lettering. In script lettering there are many points at which the strokes of the lettering cross each other. A single groove formed with such crossing elements could not be used as a sign element for the reason that the current in passing along the groove wouid follow the path of least resistance. Accordingly, at each such crossing the current would pass over the crossing without following the intervening loop which latter would consequently be left dark. In order to overcome this` diiculty the arrangements shown in Figures 5 and 6 have been devised.

In Figure 5 Vthe tube I has mounted therein a .plate I0 of glass or other transparent material.

the plate I0 as indicated in the solid lines in Figure 5 and all the down strokes I2 may be formed on thereverse side of said plate as indicated in dotted lines in Figure 5. Where these strokes join each other the plate is perforated with a small hole as indicated at I3. Accordingly, at places where the up and down strokes cross each other said strokes lie on opposite sides of the plate I0 and there will be no possibility of short circuiting the intervening loop.

The plate I0 formed as described above is then slipped into a flattened tube I4 as shown in Figure 6. The sides of the tube I4 form cover plates for the plate I0, closing the grooves on both sides thereof so as to form the restricted current path.

The plate III terminates at one end at I5 short the one electrode is sealed Within the tube I4 said tube forms a partition to prevent the current passing around the plate I0 without traversing the groove. Accordingly the current is forced to traverse the groove passing from side to side of the plate I 0 through the perforations I3.' Accordingly both portions 4II and I2 of the current' path are rendered luminous and since the plate I0 is transparent the portions I2 on the rear thereof will be visible therethrough and the lettering will, therefore, appear to be continuous.

In Figure 13 a sign is illustrated similar in conin the tube a.

ever, the lettering plate is made up in sections 3| each bearing a single letter or symbol. The letter 1n this case is also formed by a groove 5 as in the previous cases. Each section, however, bears but a single letter and the grooves are so arranged that any two sections may be placed adjacent to one another and the grooves in such adjacent sections will communicate with one another at their adjoining edges. `In this way letters may be assembled to form any desired Word or words or other symbol.

If the plates 3| are made opaque, the groove forming each letter may be arranged to terminate in perforations I3 passing through the plate 3|. The remaining portion of the groove'shown in dotted lines in Figure 13 which connects one letter with the next may be formed on the rear face of the opaque plate so as to be invisible from the front of the sign. In this manner the individual letters may be made to stand out separately from one another as is desirable in printed lettering. The same object may be accomplished, however, by forming the invisible portions of the current path of strips or wires of conducting material as previously explained.

In the embodiment of Figure '7 a plate |1 has the lettering or other symbol formed on one or both sides of the plate in accordance with the methods of Figures 1 or 5 respectively. The plate |1 is then placed within the tube between the tubes I8 of special form. Each tube I8 is formed with a at face adapted to engage the plate I1 and with a cylindrical surface fitting snugly with- One end of each tube i8 is open while the other end is closed as indicated in the figure. The tubes I8 where they engage the interior of the tube may be formed with iiattened portions |9 to provide space for the passage of current to the groove in the plate |1. The plate |1 together with the tubes |8 provide a partition which prevents the current taking a direct path between the electrodes 2 and forces it to pass along the groove in the plate |1. The tubes I8 r may be formed to identical shape so as to be interchangeable.

The current path may be formed of a tube or a groove in a plate suitably covered by another plate so as to form in effect a tube. This is emersed in a suitable gas and means are provided in the form of the electrodes 2 or the like for passing a current along said path. Where it is necessary, a partition may be placed in the tube so as to properly restrict the iiow of current to the desired path.

In the embodiment of Figure'9 two sign elements are shown arranged back to back. Two plates 20 are provided each of which may have lettering formed thereon'in accordance with Figures 1 or 5. Each of the plates 20 is enclosed in a flattened tube 2| in a manner similar to that described for Figures and 6. The tubes 2| lare each provided with a semi-cylindrical end 22 formed so 'that when the tubes are placed back to back as shown in Figure 9 their ends 22 will fit within the cover tube in which they are sealed. Each of the ends 22 has sealed therein an electrode 2. 'Ihe tube is filled with gas which also lls the interior of the tubes 2| and the grooves in the plates 20. In this embodiment the end of the tube |-may be equipped with a threaded plug element 23 and a central contact 24 so that the entire unit may be mounted in an ordinary lamp socket. One of the electrodes 2 is connected to the Contact and the other to the plug 23.

a lamp socket.

In this embodiment the current p'asses outwardly from one of the electrodes 2 along the groove in.

one of the plates 20 to the outer end of the tube thence back along the groove in the other plate 2|) to the other electrode 2. In this case, therefore, the tubes 2| form partitions to direct the iiow of the current as described.

In the embodiment of Figures 11 and 12 the lettering may be formed of a small glass tube 23 bent to' suitable shape and supported within the tube on suitable hangers 26. One end 21 of the tube 25 has a terminal wire sealed therein to provide an electrode. The other end of the tube 25 is open. A second electrode 28 is sealed in the tube I. 'Ihe electrodes 21 and 28 may be connected to the terminals of a plug mounting 29 by means of which the unit may be mounted in In this case the current after traversing the tube 24 passes back to the electrode 29 through the body of the tube The current passing through the main body of the gas in the tube will tend to render the same luminous. The current density in this part 'of the path is, however, very slight so that the luminosity will take the form of a very pale glow. The current density within the tube 25 is much greater and the luminosity in this part of the gas will consequently be much more intense. As a result the lettering of the sign will appear brightly illuminated and surrounded by a pale glow within the tube A very attractive sign may be provided in this way.

It will be seen that in accordance with this invention a sign or signal element of a small size may be formed by providing a restricted current path of the form of the sign or symbol desired. 'I'his path is then put in communication with a reservoir or container of larger capacity in which a supply of gas in proper condition may be maintained. This reservoir supplies surplus gas to compensate for any deterioration of gas in the current path. l

Insome typesof letters or symbols it may happen that three or more strokes cross each other at several points. Such a condition is illustrated in Figure l5. To properly form the symbol in this case, a plurality of plates may be used as illustratedin Figure 16. In forming the script letter G as illustrated, the rst stroke 32 may be formed in the front face of the rst plate 33. 'Ihis stroke communicates through a perforation 34 with a groove 35 on the rear face of the plate 33 or the front face of a second plate 36. The groove 35 forms the second stroke of the letter G, This stroke terminates at a perforation 31 passing through the second plate 36 to a groove 38 on the rear face of the plate 36 or the front face of a third plate 39. The groove 38 forms the third stroke of the letter. In this wayany number of strokes may be arranged to cross each other as often as necessary vby simply multiplying the number of plates. The letter unit idea described in connection with Figure 13 may also be carried out in this construction. Toward this end, the third plate 39 may be of opaque material and the rst and last ends of construction of Figures 5, 6, 9 and 10 is simplied by forming the groove 5 in one face of the inner surface of the tube 42 which corresponds to the tubes I4 and 2| respectively in Figures 6 and 10. After forming the groove, the tube may beheated until soft and then collapsed as illustrated in Figure 7 to afiat form in which onehalf of the tube forms a cover plate for the other half.

In Figure 18 the construction of Figures '7 and 8 has been simplied in a similarmanner. In this case the groove 5 is formed in the fiat face of one of the tubes i8 and the other tube provides a cover plate therefor.

While the embodiments illustrated in the drawings show various ways of constructing signs those methods may, of course, be applied to other kinds of symbols or signals or in fact to any situation in which a visible luminous indicator is desired.

While the various embodiments of this invention are illustrated in the drawings in separate figures showing these arrangements, this is for the purpose of clearness in the description thereof. It will be understood, however, that in the construction of signs or symbols the various embodiments may be combined one with the other in any desired combination. Furthermore, certain individual features or sub-combinations may be useful without the addition of other features of this invention and the employment of such features or sub-combinations is contemplated by this invention, and is within the scope of the appended claims. It is further obvious that various changes may be made, within the scope of the appended claims, in the details of construction without departing from the spirit of this invention; it is to be understood, therefore, that this invention is not limited to the specific details shown and/or described.

Having thus described the invention, what is claimed is:

1. An illuminated display element, comprising, a translucent envelope providing a gas container, a plurality of structures within said envelope each formed to provide in cooperation with and between it and the walls of said envelope a gas duct providing a narrow current path arranged to form a display figure, said structures being formed at their adjacent portions for mutual engagement with their current paths joined to formv a continuous path in communication at its end with the interior of said envelope so as to contain therewith a continuous body of gas, means obstructing flow of electric current from one part of said envelope to another except by said path, a conductinggas in said envelope and said duct and means for passing a current along :aid palh.

2. An illuminated display element compris- .ing, a translucent tubular envelope providing a gas container, a tubular insert fitting the bore l of said envelope and formed to provide in cooperation with and between it and the walls of said envelope a gas duct providing a narrow current the walls of said envelope a gas duct providing a l narrow current path arranged to form a display figure, the paths of successive inserts being arranged/iny continuation of one another to form a continuous path in communication at its end with the interior of vsaid envelope so as to contain therewith a continuous body of gas, ,means obstructing flow of electric current from one part of said envelope to another except by said path, a conducting gas in said envelope and said duct, and means for passing a current along said path.

4. In an illuminated display device of the character described, a member formed with a groove to provide a narrow current path, and a gas-containing tube enclosing said member and fitted thereto providing a cover for the groove.

5. In an illuminated display device of the character described, a pair of tubes one of which is grooved to provide a current path, the other tube enclosing said first tube and fitted thereto providing a cover for the groove, and a current-conducting gas contained in said second tube and occupying said path.

6. In an illuminating display device of the character describedfmeansproviding a narrow gas-containing channel providing a current path tracing a plurality of successive display figures, and non-gaseous conducting material in said` path between the figures providing a non-luminous conducting portion of said path.

7; In an illuminating display device of the character described, means providing a. narrow gas-containing channel providing a current path tracing a plurality of successive display figures, and a metallic conductor interposed in said path between the figures providing a non-luminous conducting portion of said path.

8. In an illuminating display device of the character described, a display element, comprising, a tubular structure closed at one end and having an end formed for matching engagement with the correspondingly formed end of a similar adjacent element in order to position such elements relatively to one another, said element being provided on its outer surface with a groove formed to trace a display figure and said groove extending to said matching end in such a posidefining a narrow path for electric current, said elements being fitted to each other in end-to-end relation with their current paths arranged in continuation of each other and fitted to the walls of said container, and means for passing a current through said path.

:10. In an illuminated display device of the character described, a gas-containing, translucent envelope, a structure withinsaid envelope having a surface fitted to the interior wall of the envelope and having a recess formed in said surface so as to be covered by said envelope, said recess being in communication with the interior of said envelope so as to receive gas therefrom and providing a narrow current path arranged to form a display figure, and means for passing an electric current along said path.

11. In an illuminated display device of the character described, a gas-containing, translucent, tubular envelope, a tubular structure within said envelope having a surface fitted to the inamaca terior wall of the envelope and having a recess formed in said surface so as to be covered by said envelope, said recess being in communication With the interior of said envelope so as to receive gas therefrom and providing a narrow current path arranged to form'a display gure, and means for passing an electric current along said path.

12. In an illuminated display device of the character described, a gas-containing, translucent envelope, a plurality of structures arranged in successive relation Within said envelope each having a surface tted to the interior wall of the envelope and a recess in said surface arranged to be closed by the envelope and providing a narrow current path communicating with the interior of the envelope to receive gas therefrom, said recesses being formed to provide display gures, and means for passing an electric current through said paths in succession.

13. In an f illuminated display device of the character described, a gas-containing, translucent envelope, a plurality of structures arranged in successive relationv within said envelope each having a surface fitted to the interior wall of the envelope and a recess in said surface arranged to i be closed by the envelope and providing a narrow ttedfor mutual engagement so as -to place said paths in continuous relation, and means for passlng an electric current through said paths in succession.

14. In an illuminated display device of the character described, a gas-containing, translucent envelope; a plurality of structures arranged in successive relation within said envelope each having a surface ntted to the interior wall of the envelope and a recess in said surface arranged to be closed by the envelope and providing a narrow current path communicating with the inte.

rior of the envelope to receive gas therefrom, said recess being :formed to provide display gures, said structures having their adjacent portions formed with irregular matching configurations tted for mutual engagement so as to place said paths in continuous relation, and means for passing an electric current through said paths in succession. K.

15. In an illuminated display device of the character described, a plate having a surface provided with a recess formed therein to provide a display figure, and a gas-containing envelope entirely surrounding said plate and engaging said surface to close said recess to form a narrow gascontalning current path therealong, and means for passing an electric current along said path.

HAROLD M. JOHNSON. ALBERT C. PERBAL.Y 

